CodeGen: MachineInstr::getIterator() => getInstrIterator(), NFC

Delete MachineInstr::getIterator(), since the term "iterator" is
overloaded when talking about MachineInstr.

- Downcast to ilist_node in iplist::getNextNode() and getPrevNode() so
  that ilist_node::getIterator() is still available.
- Add it back as MachineInstr::getInstrIterator().  This matches the
  naming in MachineBasicBlock.
- Add MachineInstr::getBundleIterator().  This is explicitly called
  "bundle" (not matching MachineBasicBlock) to disintinguish it clearly
  from ilist_node::getIterator().
- Update all calls.  Some of these I switched to `auto` to remove
  boiler-plate, since the new name is clear about the type.

There was one call I updated that looked fishy, but it wasn't clear what
the right answer was.  This was in X86FrameLowering::inlineStackProbe(),
added in r252578 in lib/Target/X86/X86FrameLowering.cpp.  I opted to
leave the behaviour unchanged, but I'll reply to the original commit on
the list in a moment.

llvm-svn: 261504

1 files changed, 2 insertions, 2 deletions

diff --git a/llvm/lib/CodeGen/ProcessImplicitDefs.cpp b/llvm/lib/CodeGen/ProcessImplicitDefs.cpp
index d27ea2f5186..ea5d2345da4 100644
--- a/llvm/lib/CodeGen/ProcessImplicitDefs.cpp
+++ b/llvm/lib/CodeGen/ProcessImplicitDefs.cpp
@@ -96,8 +96,8 @@ void ProcessImplicitDefs::processImplicitDef(MachineInstr *MI) {
 
   // This is a physreg implicit-def.
   // Look for the first instruction to use or define an alias.
-  MachineBasicBlock::instr_iterator UserMI = MI->getIterator();
-  MachineBasicBlock::instr_iterator UserE = MI->getParent()->instr_end();
+  auto UserMI = MI->getInstrIterator();
+  auto UserE = MI->getParent()->instr_end();
   bool Found = false;
   for (++UserMI; UserMI != UserE; ++UserMI) {
     for (MachineOperand &MO : UserMI->operands()) {